Newton’s Law of Cooling

Approaching equilibrium

An interactive lesson with 6 steps, about 5 minutes: you predict, drag and solve, with instant feedback on every answer. It runs in your browser and needs JavaScript.

What you’ll learn

• Newton's law: $\dfrac{dT}{dt} = -k(T - T_{\text{room}})$.
• The temperature gap decays exponentially and halves at regular intervals.
• The object approaches room temperature but never quite reaches it.

Steps

1. Cooling coffee
2. Cooling curves
3. Halving the gap
4. Finding the constant
5. After one time constant
6. Half an hour